When I was a kid I remember reading Popular Electronics magazine which started in 1954. One of the projects that
caught my eye was a design for a Tesla Coil. This was a classic design, Neon Sign Transformer, Fixed Spark Gap,
Condenser made with pieces of tinfoil sandwiched between pieces of glass and the coil.
I remember tearing apart an old TV power transformer to get the wire. I found an old neon sign in an out building
on the farm and appropriated the transformer. I used a long, small diameter cardboard form from a roll of Christmas
gift wrapping paper to make the coil. The arc gap was made from two nails spaced about a half inch apart.
The thing didn't do much but make a lot of noise and tear up the picture on the TV.
Fast forward some 50 years and I still have a fascination with Tesla Coils. Since I don't have a synchronous motor to
build the arc gap I thought I would try building a coil that uses a large transmitting type vacuum tube. The ham
radio junk box has lots of big tubes and several large plate transformers scrounged at ham radio flea markets.
The following are some pictures of the coil. I will add the circuit diagram of the coil and a schematic of the staccato
controller when time permits. The coil generated a one foot spark on the initial power up test. I imagine a longer
spark could be obtained if I play with some values of circuit such as size of feedback winding, value of capacitor used
to tune the primary etc.
Homemade jig to wind the coil secondary.
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2000 VAC plate supply transformer for the 833A tube.
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Capacitor and primary winding of the coil.
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833A tube and primary resonating capacitor.
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833A tube, primary resonating capacitor and coil primary.
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Front view of the completed coil.
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Coil generating a one foot spark.
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